1. Field of the Invention
The present invention relates broadly to apparatuses and methods for allowing a moving user to track his or her own movement over time and for actively assisting the user in returning to an earlier location. More particularly, the present invention concerns an apparatus and method for allowing the moving user to automatically periodically determine and store his or her own current geographic locations over an extended period of time, and to display the series of such locations as an indication of the user's path of travel. Additionally, the present invention is adapted and operable to actively assist the user in returning to an earlier location, either by traveling back along the path earlier traveled or by traveling along a more direct route.
2. Description of the Prior Art
It is often desirable for a user to be able to determine his or her own current geographic location, such as, for example, when hiking, climbing, running, or otherwise traveling through unknown or unfamiliar areas. This is accomplished in prior art devices using global positioning system (GPS) technology, wherein signals are received from a plurality of orbiting satellites and, based thereon, location is determined with respect to the satellites. Such GPS-based location-determining functionality is available in hand-held prior art devices that can be carried by the user on his or her person.
It is also desirable, however, for the user to be able to view his or her previous locations so as to better understand his or her path of travel over time. It will be appreciated that such information is particularly useful when the user desires or needs to backtrack or otherwise return along this path of travel. It will also be appreciated that under some circumstances, such as, for example, when traveling through rapidly changing terrain, locations must be determined and stored relatively frequently in order to provide the most complete and useful record. Furthermore, in order to accommodate extended travel, the process must allow for determining and storing locations in this manner for as long a period as possible. Prior art devices exist for determining and storing locations but, unfortunately, suffer from a number of drawbacks and disadvantages.
Hand-held prior art devices exist, for example, that allow the user to determine his or her current location and, if desired, designate the location as a “waypoint”. The waypoint is then stored in memory and is available for later recall. Unfortunately, the designation of waypoints requires active participation by the user. Furthermore, the maximum number of waypoints that can be designated is likely to be extremely limited because the waypoint concept generally refers to a very limited number of special locations designated for very particular purposes, not an unlimited number of non-special locations designated merely for general record-keeping purposes. It will be appreciated that a user, relying on waypoints to provide a record of his or her previous locations may allow undesirably long periods of time to pass between designations. When the user does remember to make a designation, he or she may remove the electronic device from its protective or carrying environment only to find it impossible to quickly achieve the satellite lock necessary to determine the current location, and so the user must travel still further until the required lock can be established. Also, in order to designate waypoints, the device must either be left on continuously, thereby draining power and severely limiting both the amount of time in which new waypoints may be designated and the amount of time in which stored waypoints may be recalled, or the device must be turned on and off each time a designation is made. Turning the device on and off in this manner can itself result in a substantial power drain, and so the frequency with which waypoints are designated must be reduced. Thus, these particular prior art devices do not provide a practical and reliable mechanism for creating a record of the user's previous locations in such a manner as to allow for better understanding his or her path of travel.
More capable hand-held prior art devices exist that allow for creating a more complete and reliable record of previous locations automatically and without the drawbacks associated with using waypoint technology for this purpose. Unfortunately, these prior art devices quickly deplete their battery power, and once the power fails, no further locations are determined and the user can no longer display the record of previous locations. If the user travels for longer than a few hours with no ability to charge the battery, he or she will not be able to display the path of travel if the need arises to backtrack, creating a potentially dangerous situation.
Large-scale prior art systems also exist that allow for remotely tracking the locations of multiple vehicles over time. Such systems typically comprise a plurality of location-determining mechanisms, each being affixed to or otherwise associated with one of the remote and moving vehicles, and a central receiving and processing station for receiving location data from the location-determining mechanisms and for plotting such location data over time. Unfortunately, because the location-determining mechanisms are carried on vehicles, there are none of the weight, size, or power consumption restrictions that a hand-held device would require. Thus, internal processors have ample power and antennas are both large and fixed. Furthermore, while providing the location data to the central station for plotting does provide a record of travel over time to those at the central station, returning this information to the vehicle would require an additional receiver, memory, and display at the location-determining mechanism, and an additional transmitter at the central station. It will therefore be appreciated that these prior art systems are neither useful nor feasibly adaptable for solving the present problem of allowing hikers and other traveling individuals to save and recall their previous locations so as to better understand their path of travel.
Due to the above-identified and other problems and disadvantages in the art, a need exists for an improved apparatus or method for allowing a moving user to track his or her own movement over time and to assist the user in returning to an earlier location.